Electric tracker mechanism



ATTDPNEKS.

BEST AVAELABLE cop\ G. E. BROWN ELBCTRIC TRACKER MECHANISM Filed Nov. 15'. 1923 BESTAVUBLE SOP;

Patented Aug. 24, 1926.

UNITED STATES cAaL n. BROWN, oFcoLUMBUs, OHIO.

ELECTRIC TRACKR mnc rnmsm.

Application filed November 15,'1923, Serial No. 674334.

My invention relates to tracker mechanisn for such instruinents as player pianos, player organs, or other devices which are operated by means of selected electri c circuits, in which a perforated paper strip is passed over a tracker mechanism, with the perforations forming the circu'it selecting elements. I

'In the production of music by clectric players, one of the great ditliculties has been the quick and positive clos in'g of the desired circuits, since a positive contact to close the' selected circuits is a .prime requisite. This' is indicated in electric player pianos, 'for example byf fmuddy efi'ect, of the various notesjmerging into each other or' lagging behind part.

It ism'y object to 'provide' abrnsh and contact mechanism in devi'eso'f't e type noted whichgives'firmcircuit closures at all times( Amon fther pints of my invention, I provi e"the traiker bar itself with spac'ed insulat'ed circujitt'erminal 'contactpins, and employ a brush yvliichis common to all circu'itsfinother words, provi ding a ,around return from ele ct1 'o-`magnets, to the brush. y p I The brush itself forms an important part of my invention, and I -ormit from a large number of fine wires of conduct-iv natriah said wir-es cut offat the end to form a broa'd Contacting surface, to rest` n the perforated roll as it.is ted over the tracker. In other words, beside binga brush, according to electric terminology, my device 'is a wire brush in common terminology. Because of the use of such a mechanisin I am able to employ weighting means or some other common means of pressing the brush against the tracker, to the end of assuring contact. In all instances in the past where contact brushes have been formed of bunches of wires for use with tracker mechanisms, each brush has been individual to one circuit, and hence no common -weig thing, mechanism or common mounting mechanism could be used, and the Construction has been refined to the extent that a positive operation of the brush at all times has not been possible from a practical point of view.

The use of a brush spanning all contact pins or some substantial number of them, acts in addition as a means for holding the tracker paper down on the tracker bar. The shitting of the paper laterally, where there is an individual brush for each circuit, and

a long contact plate on the tracker, is likely toprevent the brushes from making any contact. which is not possible with :1 brush extending the whole length of the tracl-zer, and co the tracker equipped with individual circuit contact pins', since there will' always be a brush contact,

I Also inelectric player pianos. for examp`e, therequirement is often present for the closing of a number of circuits at the same time, and' by my invcntion this is completely po:- sible while with separate brushes each one acting independently, the exact simultaneous action isnot always possible, with the result of thejbl urring or muddy elte'ct already I accomplish the objects and attain the points i noted 'above 'by thfat certain construction and arrangement of ,parte to be h r. imam-mor specifically pointed out and claimed;

"In the drawing 'Figurejl is a vertical section showing the mechanisin. i F igurefl *isa'ront elevation of the mcchan sm 4 I haveshown a tracker bar 1, having a. series of insulated bn actpins 2, 2, each one forming part of a s'ingleelectric circuit, as {attachment} ofwirs & The' pins have conta ;face thetop level of the tracker jFpr' illiistration I have 'clizigramrhatie ami as jeearana nt 'e 'which is onnected'to *wire 3, anetaret connected to ground 5.

It will be understood that a strip of perforated paper will pass over the tracker, said perforations serving' to expose the contact pins to a contact member engaging the paper, directly over the contact surface of the pins.

In -its preferred form this member comprises a rock shaft 6, mounted in brackets 7, 7, at the ends of the tracker, and carrying a brush holder 8. This brush holder may be bent over the shaft, and crimped over the wires of the brush. The wires are arranged in the form of a long narrow wire brush, as at 9, the extended assembly of wires being held by the holder. As shown the holder, the shaft or the wires will be grounded, giving to the brush the character of a common return for all circuts that pass through the tracker pins.

The ends of the wires are cut away as at 10 for forming a fiat contact, covering an area inclusive of all of the contact pins.

- ters Patent, is ::E

In order to enforce a contacta nd prevent the Wires of the brush as they rest on the paper passing over the tracker, from jumping the perforations, and hence not closing the desired circuits, I add a weight' mecha nism to the brush. This Weight mechanism is formed of a heavy rod 11, held in a' metal strip 12, which metal strip is. riveted to, the brush holder. The rod then rests on' the wires, and bands them toward the tracker and also acting on the rock shaft, tends to hold the entire brush down against the tracker. i

`While I might suhstitute a spring operating on the rock shaft, or some other form ot' pressure means, the weight form of control has the advantage in addition'to that of maintaining contact of actually resting on the wires and keeping them in place, as .Well as, if desired, partially fieXing them from their natural extension fromthe holder. i I do not desireto be ekcluded from the doctrine of equivalents in, the Construction of my claims that follow because of my failure to point out modified Construction& Having thus described my invention, what I claim as new and desire to secure bytL'etl. In combination', a tracker banja series of interspaced electric contacts in the' tracker adapted to be selectively exposed by' a perforated sheet passingoveiythe tracker bar,

- and a non-selecti've continuo'us contact hrush to close circuits through said,contacts, said brush comprising a single holder and 'Wres in the holder, said wires being arranged to wipe any exposed portion of the tracker bar between theoutsde Contacts. V a i 2. In combination', a tracker bar, a series' of interspaced electric contacts in the tracker adapted to be selectively;,exposedl'through perforations in a sheet passingbver the tracker bar, and 'a non-selective continuous w with the tracker-. I

%597950 easr artament cosi contact brush to close circuits through said Contacts, saidbrush'comprisinga ,single holder and wires in the' holder, said Wires being arranged to wipe any exposed portion of the tracker bar within the extreme outside Contacts on the tracker bar, and means for impellngf the Wires on the holder toward the tracker :bar to secure a firm engagement and to hold the perforated sheet against the tracker bar. I

3. In combination, a tracker bar, a series of interspaced electric Contacts in the tracker adapted to he selectvely exposed by a perforated sheet passing over the tracker bar and a non-selective contact hrush to close circuits through said Contacts, said brush comprising a holder and wires in the holder, said wires being arranged to wipe the tracker bar or the perforated sheetthereon over the entire space occupied by said series of Contacts, means for pivotally mounting the holder and means :for impelling the holder and wires toward the tracker to secure a firm engagement and to hold the sheet down onthe trackersaid; means comprising a weight mounted so as toten'd to Swing the holder toward contact position 41 In combinatiom a [tracker bar; a'series y of -interspaced electriccontacts in the tracker adapted to be ,selectively exposed by a 'per: forated sheetjpassing over the 'tracker' bar, and a -non-selective contactbrush to close circuits through said contacts; said brushcomprisin a holder and wires in the holder, said wiresheing arranged' to wipethe tracker bar or the perforated sheetthere'on over the entire space occupied by said series ofrontacts, means for pivotally mounting the holder and a'weight Suspended against said wires and Secured to the ho1der,` Whereby the wires are pressed toward the .tracker.

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